By Kathleen Berger, Executive Producer for Science and Technology

A massive study discovers the diabetes risk rises after an infection with COVID-19. Even mild SARS-CoV-2 infections can amplify a person’s chance of developing diabetes.

“We saw very early on in the pandemic that when a lot of people get COVID-19, they have this really very high spike and blood sugar. And we started getting reports that people are also having diabetes problems, even kids getting insulin dependent diabetes, or diabetes type 1, and diabetes type 2 across all age groups, even in kids,” explained Ziyad Al-Aly, MD, chief of research and development at the VA St. Louis Health Care System and a clinical epidemiologist at Washington University. “So, we decided to take a look. We decided to have a more comprehensive analysis to try to understand – do people with COVID-19 have a higher risk of developing diabetes.”

Al-Aly and his collogues analyzed the de-identified medical records of veterans in the database maintained by the U.S. Department of Veterans Affairs. The study examined the records of more than 180,000 VA patients who tested positive for COVID-19 between March 2020 and September 2021. The records were compared with more than 8 million VA patients who either had not tested positive or received VA medical care in the two years before the pandemic.

The study found that out of every 100 people who tested positive for the virus, two people were later diagnosed with diabetes.

“It’s compellingly clear that infection with SARS-CoV-2 could lead to increased risk of diabetes, even up to a year later,” said Al-Aly.

The study discovered that people who had had COVID-19 were about 40% more likely to develop diabetes up to a year later. Even mild or asymptomatic SARS-CoV-2 infections increased a person’s chance of developing diabetes. Most had type 2 diabetes rather than type 1.

“In our population we saw the increased risk of diabetes, most type 2, but it doesn’t really mean that type 1 is not happening,” Al-Aly explained. “Quite a bit of diabetes type 1, especially in the children population.”

With type 2 diabetes, the pancreas makes insufficient amounts of the hormone insulin, which regulates the movement of sugar in cells. When insulin levels are too low, sugar levels can get too high in the bloodstream, potentially leading to disorders of the circulatory, nervous and immune systems. Al-Aly believes diabetes develops when the body’s immune system responds to the SARS-CoV-2 virus, triggering inflammation that could then impair insulin secretion and sensitivity.

And because the study found a heightened risk of diabetes so long after infection, Al-Aly said it appears as though little, if any, of the effects may be reversible.

Al-Aly recommends that anyone who has been diagnosed with COVID-19 get screened for diabetes, adding that the earlier one is diagnosed, the better their outcome.